Chohne

The major point of entry for one-carbon fragments into substimted folates is methylene tetrahydrofolate (Figure 45-16), which is formed by the reaction of glycine, serine, and choHne with tetrahydrofolate. Serine is the most important source of substituted folates for biosynthetic reactions, and the activity of serine hy-... 

Dale PJ, SamantiUeke AP, Shivagan DD, Peter LM (2007) Synthesis of cadmium and zinc semiconductor compounds from an ionic liquid containing chohne chloride and urea. Thin Sohd Films 515 5751-5754... 

Tocotrienols, gamma Oryzanol Phosphatidyl chohne Antioxidants Controls liver cirrhosis and helps in effective liver detoxification (Bruni, 1988). Protectant against hver damage (Kidd, 1996). Antioxidant enzymes prevent hpid peroxidation and helps protecting the liver cells from damage. 

PANFILI G, MANZI P, COMPAGNONE D, SCARCIGLIA L and PALLESCHI G (2000), Rapid assay of chohne in foods using microwave hydrolysis and a choline biosensor , J Agric Food Chem, 48, 3403-7. pant I and trennery v c (1995), The determination of sorbic acid and benzoic acid in a variety of beverages and foods by micellar electrokinetic capillary chromatography , Food Chem, 53(2), 219-26. pare j r j and Belanger j m r (1997), Instrumental Methods in Food Analysis. Series Techniques and instrumentation in analytical chemistry - Vol. 18, Amsterdam, Elsevier. 

Esko, J.D., Wermuth, M.M., and Raetz, C.R., 1981, Thermolabile CDP-chohne synthetase in an animal ceh mutant defective in lecithin formation. J. Biol. Chem. 256 7388-7393 Esko, J.D., Nishijima, M., and Raetz, C.R., 1982, Animal cells dependent on exogenous phosphatidylchohne for membrane biogenesis. Proc. Natl. Acad. Sci. USA. 79 1698-1702 Exton, J. H., 1994, Phosphatidylchohne breakdown and signal transduction, Biochim. Biophys. Acta 1212 2642. 

Apoptosis is induced by chohne deficiency in fetal brain and in PC 12 cells. Brain Res. 

Houweling, M., Cui, Z., and Vance, D.E., 1995, Expression of phosphatidylethanolamine N-methyltransferase-2 cannot compensate for an impaired CDP-choUne pathway in mutant Chinese hamster ovary cells. J. Biol. Chem. 270 16277-16282 Ishidate, K.. 1997, Chohne/ethanolamine kinase from mammalian tissues. Biochim. Biophys. Acta 1348 70-78... 

McMaster, C.R., and BeU, R.M., 1997, CDP-chohne 1,2-diacylglycerol chohnephospho-transferase. Biochim. Biophys. Acta 1318 100-110... 

Yen, C.L., Mar, M.H., and Zeisel, S.H., 1999, Chohne dehdency-induced apoptosis in PC12 ceUs is associated with diminished membrane phosphatidylcholine and sphingomyelin, accumulation of ceramide and diacylglycetol, and achvation of a caspase. FASEB. J. 13 135-142... 

Epididymis Carnitine Inositol Phosphatidylcholine Cholesterol Glycoproteins Facihtates acetyl-CoA oxidation by spermatozoa (Chapter 9) Precursor for formation of phosphatidyhnositol bisphosphate Buffer to maintain pH and a source of chohne Stabilises membranes They coat the surface of the sperm to protect against IgA... 

Scheme 6.1 The AChE catalyzed hydrolysis of ACh to chohne and acetate.

Tolazoline is a weak, reversible a-adrenoblocker that lowers resistance of peripheral blood vessels and elevates venous capacity. However, it also exhibits 8-adrenomimetic activity, which consists of the stimulation of cardiac work and is manifest as tachycardia, chohn-ergic activity, which consists of stimulation of the gastrointestinal tract, and histamine-Uke activity, which consists of stimulation of gastric secretion. 

Luine VN, Khylchevskaya RJ, McEwen BS Effect of gonadal steroids on activities of monoamine oxidase and chohne acetylase in rat brain. Brain Res 86 293-306, 1975... 

Fig. 6.11. Formation and function of diacylglycerol. The figure schematically shows two main pathways for formation of diacylglycerol (DAG). DAG can be formed from PtdInsP2 by the action of phospholipase C (PL-C). Another pathway starts from phosphatidyl chohne. Phospholipase D (PL-D) converts phosphatidyl choline to phosphatidic add (Ptd), and the action of phosphatases results in DAG. Arachidonic add, the starting point of biosynthesis of prostaglandins and other intracellular and extracellular messenger substances, can be cleaved from DAG. PKC protein kinase C Ptdins phosphatidyl inositol.

In cortical cultures, AMPA receptor activation is also linked to chohne release and inhibition of PtdCho synthesis (Gasull et al., 2001). In contrast, the selective stimulation of KA receptors has no affect on the release of choline and does not reduce PtdCho synthesis. Sensitization of AMPA receptors plays an important role during this process. Thus in the presence of cyclothiazide (CTZ), an inhibitor of AMPA receptor desensitization (Bertolino et al., 1993), AMPA receptor over stimulation becomes neurotoxic after 24 h of treatment. However, significant neuronal death does not occur until the first hour of treatment. In contrast, stimulation of non-sensitized AMPA receptors causes a marked inhibition of PtdCho synthesis within 5 min of treatment. These observations suggest that AMPA-mediated inhibition of PtdCho synthesis precedes membrane permeability changes that may cause excitotoxic necrotic neuronal cell death (Gasull et al., 2001). 

Lecithin is the main dietary source of choline. The U.S. National Academy of Science s (NAS) Food and Nutrition Board recently underscored the importance of lecithin in human nutrition by assigning chohne (the vitamin component of PC) a dietary reference intake (DRI) in 1998 (244). Although it is true that lecithin and choline are present in a variety of foods, the specific amount of lecithin and choline in foods is currently unknown. At this time, no comprehensive analysis of choline in the food supply exists. Such an analysis is, however, underway and it is estimated that the extensive USDA database of foods will be fully analyzed for choline content by 2005. The analysis will include all forms of choline found in food. 

Differences in nutritional effects between PLs and TAGs can be caused by several factors not related to their fatty acid composition, such as the presence of a phosphate group and a nitrogen base (mainly chohne) that may interact in several metabolic pathways (82). Moreover, several glycerophospholipid preparations studied can contain other components such as cholesterol, cerebrosides, sphingomyelins also depending on their source, method of isolation, and purification. These components may also affect the nutritional properties. In this chapter, the metabolic fate of constituent fatty acids of PLs and TAGs will be compared. 

CN.S rnyehn contahis more chohne and plasrnalogens tlian PN.S rnyehn (Garbay et al., 2000). 

Cholinesterase During the further course of disease, chohn-esterase decreases in relation to its longer half-life and likewise allows a reliable assessment to be made of the remaining liver function. (s. p. 103)... 

Yamasaki, K. Kikuoka, M. Nishi, H. Kokusenya, Y. Miyamoto, T. Matsuo, M. Sato, T. Contents of lecithin and chohne in crude drugs. Chem. Pharm. Bull. 1994, 42, 105-107. 

Potter, P.E. Meek, J.L. Neff, N.H. Acetylcholine and chohne in neuronal tissue measured by HPLC with electrochemical detection. J. Neurochem. 1983, 41, 188-194. 

Patrick, J. Heinemarm, S. Members of a nicotinic acetyl-chohne receptor gene family are expressed in different regions of the mammalian central nervous system. Cell 47. 1987, 48, 965-973. 

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